Hello, yes it's got 97 octane fuel, have tried looking at the base gasket with wd40 looking for air bubbles, or drawing air in, well what's next gotta be the ignition, flywheel will be off for inspection tom, any ideas with that? got the correct jets according to GG UK 118 and 35 and needle support brass thingy 270k, i love these gasers but what a pain they can be when there just not right. Still think its the carb body myself takin it for a proper mech to look at see what he think's.

The plot thickens, was advised by a guy today that he reckons is mechanical noise, well ie the little end bearing, He reckon so because the knock/pink happens when you 'back off' the revs and not under load when the revs are increasing. he is right when the bike is staitionary, but when i am riding it, and say do a hill climb, i am sure i can here it then too. sure i am not backing it off then on a hill climb. The bike is literally like new condition but hey some things are not always right from new i suppose. well i am unhappy now with no bike to ride ; - ( dummys on the floor with GG for the moment...

j

I think your maybe starving the bike of fuel

at high rpm you drain the bowl on delorto as it doesnt fill very quickly.

for last years ssdt I fitted a 300 float valve to stop this happening on the fast tracks.

bear in mind the main jet feds via the drain bolt, the pilot jet will be higher and this may explain why it pinks when you shut off after a long climb.

I doubt its mechanical on an 09

Baldilocks you think i need a bigger main jet? 118 in athe moment GGUK say that is right some other guy said try a bigger one?

thanks

j

Baldilocks you think i need a bigger main jet? 118 in athe moment GGUK say that is right some other guy said try a bigger one?

thanks

j

No he says float valve, the brass "jet" the float needle sits in, I have changed these before on 300s.

ian

Ah yes GGUK mentioned this, i took it out, float valve checked its number, 270k they told me to check that it was a 270k and it is, took carb to my mate who's a mechanic he checked it over and said it was fine, just blowed out the pilots like i had done, he mentioned ignition but i cant remove flywheel without a puller which is best part of 50quid. it runs the same on both maps. He Also mentioned water pumpshaft could be broke getting hot preignition, Dont think it is though the cylinder head is running at 60degrees and i reckon would be much hotter if the water was not movin around the engine. looking like it's gonna be an engine out job...;-9...first i may try and find a puller for the flywheel.

Ah yes GGUK mentioned this, i took it out, float valve checked its number, 270k they told me to check that it was a 270k and it is, took carb to my mate who's a mechanic he checked it over and said it was fine, just blowed out the pilots like i had done, he mentioned ignition but i cant remove flywheel without a puller which is best part of 50quid. it runs the same on both maps. He Also mentioned water pumpshaft could be broke getting hot preignition, Dont think it is though the cylinder head is running at 60degrees and i reckon would be much hotter if the water was not movin around the engine. looking like it's gonna be an engine out job...;-9...first i may try and find a puller for the flywheel.

Ah yes GGUK mentioned this, i took it out, float valve checked its number, 270k they told me to check that it was a 270k and it is, took carb to my mate who's a mechanic he checked it over and said it was fine, just blowed out the pilots like i had done, he mentioned ignition but i cant remove flywheel without a puller which is best part of 50quid. it runs the same on both maps. He Also mentioned water pumpshaft could be broke getting hot preignition, Dont think it is though the cylinder head is running at 60degrees and i reckon would be much hotter if the water was not movin around the engine. looking like it's gonna be an engine out job...;-9...first i may try and find a puller for the flywheel.

In order to eliminate ignition as a possibility, a puller should be your next investment. It's not unusual for the flywheel hub to slip a little on the tapered shaft and cut into the key enough to throw off the timing. This generally happens on new bikes after a few heat cycles as Trials bikes have heavy flywheels and the driveline takes some severe jolts. It's always a good idea to check fasteners like the flywheel bolts and spokes as they tend to "relax" after initial assembly and bedding in.

Jon

GG flywheel pullers I sell for about 9 quid.......

The 270K is the needle jet. The float valve, is the "orofice" the float needle locates in.

It's unlikely to be wrong, but check (it unscrews).

It was an issue on the VHST Dellortos, bit you don't have that carb , as std.

Edited March 1, 201016 yr by motomerlin

Have you checked the float height ?

also try cleaning the in line filter thats in the carb body where the fuel hose connects.

As motomerlin said you dont need to spend

Hello thanks for all the help, carb is fine, i am sure its the little end, the noise is heard after you rev the bike,shut off and it knocks, but i cant look at it myself at the moment due to work commitments, mech has it right now i am hoping to know by tom night what is wrong with it. the guy that had it from new was not a trials rider, by looks of it he put it on the road and was just posing about on it, maybe give it too much stick before it run it proper and developed a top end bearing problem?

j

It's fixed at last...After replacing the base gasket to a 1mm version, and fitting and head spacer, and giving top end a good decoking it's running like a dream :-)..., carburation is now spot on too, I think what was causing the problem the previous owner +50 mid life crisis looking for a new hobby, plenty of cash but no idea, come on we have all done it.., who rode it five times at the most, was inexperienced and had mixed the two stroke with way too much oil, the top end was really badly gummed up, once warm all the carbon was lighting fuel, not sure really but i just know now i have a great hardly used bike now and am as happy as a pig in sh*t after all the earlier problems.... i just love gasers again....you just cant beat em..with the head spacer made it much eaiser to kickstart too. Did notice that the barrel castings and engine casings also didn't line up 100%, it could have been the base gasket that did the trick but who cares, happy riding..

My new 08 300 is knocking on let off also, is it worth taking the head off and cleaning her up a bit?

They will all knock a bit if you completely chop the throttle to the off position.

My 2010 setup with Dellorto is 38 pilot 118 main with 94 pump gas mixed 30% with 109 octane race fuel, 80:1 premix. This is for North America. Runs great.

My new 08 300 is knocking on let off also, is it worth taking the head off and cleaning her up a bit?

Try checking the pilot jet first. A lot of the Pros come with a #35 pilot, which in some cases can lead

to slight knocking when the throttle is quickly closed, especially in hotter weather. You might try a

#38 and re-adjust the fuel screw to see if that fixes it.

Jon